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Difference between revisions of "Half Equation"

(Examples)
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===Examples===
 
===Examples===
[[Balanced Symbol Equation]]: 4Li + O<sub>2</sub> → 2Li<sub>2</sub>O
+
[[Balanced Symbol Equation]]: 2Li<sub>2</sub>O 4Li + O<sub>2</sub>  
  
 
'''Half Equation''' at [[cathode]]: Li<sup>+</sup> + e<sup>-</sup> → Li
 
'''Half Equation''' at [[cathode]]: Li<sup>+</sup> + e<sup>-</sup> → Li
  
 
'''Half Equation''' at [[anode]]: 2O<sup>-2</sup> → O<sub>2</sub> + 4e<sup>-</sup>
 
'''Half Equation''' at [[anode]]: 2O<sup>-2</sup> → O<sub>2</sub> + 4e<sup>-</sup>

Revision as of 07:04, 3 January 2019

Key Stage 4

Meaning

A half equation is a type of symbol equation which shows how individual ions gain or lose electrons at an electrode during electrolysis.

About Half Equations

In half equations only one ion is considered at a time, or the changes at one electrode.
Half equations use the letter 'e' to represent electrons.
Half equations can be taken from balanced symbol equations.

Examples

Balanced Symbol Equation: 2Li2O → 4Li + O2

Half Equation at cathode: Li+ + e- → Li

Half Equation at anode: 2O-2 → O2 + 4e-